A method for producing hydrogen from a feedstock comprising water and at least one fuel selected from the group consisting of hydrocarbon fuel, natural gas, propane, naphtha, hydrocarbons with <100 ppm sulfur by mass, and mixtures thereof, comprising:
- in a reactor, producing hydrogen by steam reforming said fuel;
- and
- purifying said hydrogen with a pressure swing adsorption (PSA) system;
- wherein prior to said producing, no pretreatment of said fuel to remove at least one impurity selected from the group consisting of sulfur and molecular oxygen and mixtures thereof is carried out;
- wherein a molar ratio of water molecules to carbon in said feedstock ranges from 3:1 to 8:1;
- and
- wherein said reactor comprises:
- a unitary shell assembly having an inlet and an outlet;
- a flow path extending within said shell assembly from said inlet to said outlet, said flow path having a steam reformer section with a first catalyst and a water gas shift reactor section with a second catalyst, said steam reformer section being located upstream of said water gas shift reactor section;
- a heating section within said shell assembly and configured to heat said steam reformer section;
- and
- a cooling section within said shell assembly and configured to cool said water gas shift reactor section;
- wherein said first catalyst comprises a steam reforming catalyst;
- and
- wherein said second catalyst comprises a water-gas shift catalyst.